How odd is it to be trapped inside the parallel, ever-accelerating cycles of amnesia and nostalgia that mark American culture these days? Pretty odd. You'd be forgiven, for example, for experiencing a certain degree of confusion, if not outright philosophical whiplash, about the attitude we're currently expected to display toward the art and architecture that emerged two decades ago, in the middle of the 1990s.

At L.A.'s Museum of Contemporary Art, a new show called "Don't Look Back: the 1990s at MOCA" — alternate title "Please Do, Actually, Look Back" or "You Might Enjoy a Spin Through the Gift Shop When You Are Done Looking Back" — is celebrating the work produced in that decade by Paul McCarthy, Cady Noland, Sarah Sze and other artists.

Nearly 400 miles due north, meanwhile, the San Francisco Museum of Modern Art will on May 14 open a massive new $305-million wing by the prolific Norwegian firm Snohetta that doesn't merely extend but performs a smooth lobotomy on the museum's existing building, which was designed by the Swiss architect Mario Botta and opened in — you guessed it — 1995.

There are all kinds of practical reasons the museum deemed this surgery necessary and even urgent. The 235,000-square-foot addition, which stacks seven stories of gallery space and three administrative levels behind the old brick-wrapped Botta building, is anchored by a wide lobby stretching across its second floor. Forging an open connection between that space and the entry to the old building along Third Street seemed to require that the hulking staircase filling Botta's atrium be removed.

Taking its place is a much smaller staircase by Snohetta, clad in maple, that leads directly from the new lobby down to the old one. The really striking quality of that moment of aggression toward the Botta building is that is seems altogether out of character with the rest of the addition. In almost every other way the Snohetta design is handsome, carefully intelligent, self-effacing and agreeable.

Throughout the new wing, the architecture never really has an opportunity to approach, let alone challenge, the primacy of the art. For the most part the galleries are roomy, minimalist and crisply effective, light filtering down from coved ceilings.

The raised Snohetta lobby, with its polished terrazzo floors, operates as a kind of gleaming way station between a new sidewalk-floor gallery that is open to the public without ticketing (called the Roberts Family Gallery, it now holds Richard Serra's sculpture "Sequence," from 2006) and the higher floors of the new building.

SFMOMA

The expanded new SFMOMA at night.

The expanded new SFMOMA at night.

(SFMOMA)

The only interior moments of architectural drama come along the eastern edge of the new wing -- in the windows offering carefully arranged views toward San Francisco Bay and staircases, again in maple, that grow narrower as they move higher -- and the bathrooms, which are flooded with intense monochromatic color, a different shade for each floor.

Outside, as a presence in the cityscape, the Snohetta tower, clad in rippling off-white panels of fiberglass-reinforced polymer, is even more apologetic about both its ambition and its bulk. It is everywhere shaved off and pinned back, forever curving away from you as you stand on its one of extensive outdoor terraces and try to assess its scale and civic personality.

The contrast between that attitude and the way the other new towers in San Francisco's thickening skyline carry themselves is extreme. As you look east from the higher of the two terraces, on the seventh floor, you are confronted with the aggressively large and broad-shouldered dark-glass form of a new 26-story office building at 2nd and Howard streets, designed by Thomas Phifer and leased by LinkedIn. The SFMOMA tower is by comparison all stooping form and retreating volume.

The unfortunate symbolism of this relationship — the cultural building practically tripping over itself to stand down and out of the way, the new commercial buildings blithely taking up as much space in the sky as they can — seems typical of the balance of power in the new, money-drenched San Francisco. (The arts are not so much on the run here — how could they be, when there is so much wealth on so many boards of trustees? — as keenly aware of their place in the pecking order.)

Henrik Kam / SFMOMA

Expansion of the new SFMOMA, opening May 14, 2016, from the back.

Expansion of the new SFMOMA, opening May 14, 2016, from the back.

(Henrik Kam / SFMOMA)

It also qualifies as the great surprise of the new Snohetta wing. The renderings suggested it might be some giant iceberg or museum-world cruise ship, sliding its overwhelming bulk into port just behind Botta's brick-wrapped wedding cake. In fact the final product is quite efficiently tucked away on a tricky and constrained site. From the sidewalk in front of the old building it is impossible to see even the top floor of the new wing.

Around back and down again at ground level, the Snohetta building comes alive in a complex attempt to simultaneously squeeze the most out of its small footprint and open itself up to the surrounding streets. Though plenty of visitors are expected to keep using the 3rd Street entrance, coming up through the Botta atrium, a second and equally important entry now opens alongside a kind of back alley onto Howard Street. Two sets of stairs, one inside stepping up from the free gallery with the Serra and the other outside, under the overhang of the new wing, lead from the street up to the main lobby floor on Snohetta's level two.

In that deftly handled sequence of spaces, some inside and some outside, some urban and some purely architectural, you get a clear sense of the heights Snohetta is capable of reaching when given real room to operate. (The firm, which first made a name for itself by winning a 1989 design competition for a new Alexandria Library in Egypt, is one of seven finalists for the plum Obama Presidential Library commission in Chicago.)

Still, even as the intelligence of that part of the design lingers in your mind, the relationship of the new wing to the existing building, of Snohetta to Botta, remains tough to figure. There is both real deference and an odd sort of architectural fratricide in the way the new building treats the old one.

In order to preserve the galleries in the older building, which the museum clearly needs, as well as its profile in the cityscape, SFMOMA has gone to great lengths to protect and honor the Botta. The gallery floors of the new wing are lined up exactly with those of the old one. In the public and circulation spaces the equation is reversed. With the stair gone, the old structure operates as an emptied and oversized entry hall to the new wing, a baggy antechamber whose proportions now feel all wrong, even as it gets a better quality of reflected sunlight than it used to from above.

So look back, SFMOMA seems to be suggesting. Embrace the Botta building and its importance. But also don't look back, because the architectural integrity of that building, which relied to a large degree on that staircase, isn't crucial in the end, at least not in the museum's judgment.

SFMOMA has killed its 1995 building to save it, or saved it to kill it. Take your pick. It's a strategy that might make sense if the Botta were layered or complex enough as a work of architecture to survive this kind of dismantling. But it's not. It was never an especially persuasive or stirring building before – it was fine, it spoke of a moment -- and looks even less sure of itself now.

The new wing, for its part, is left to fold and bend itself in a series of gymnastic maneuvers to fit into the space left over behind the hollowed-out Botta. It's an odd, nearly perverse bit of reasoning, at least for anyone who cares about architecture: We're going to give pride of place in the urban sequence, the museum leadership has decided, to a building whose basic architectural logic, which flowed directly from the presence and solidity of the old stair, we find entirely disposable.

All of which leads to an obvious question: Should the museum simply have knocked down the older building and started from scratch on a prominent and roomy site? My trip to San Francisco has left me thinking it probably should have.

And not simply because the way it has treated the Botta seems the worst of both worlds. Far more because what San Francisco needs at the moment is a full-on and unapologetic expression of contemporary architecture and culture, granted both the space and the institutional permission to make its own statement, to be surprising, challenging, occasionally irrational and maybe even downright weird.

A version of this article appeared in print on April 28, 2016, in the Entertainment section of the Los Angeles Times with the headline "SFMOMA: BALANCE OF POWER - Balance of power - An aggressive bend and fold to new wing at SFMOMA - ARCHITECTURE REVIEW" —
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